on larvae of Flustra, [466];
on Cristatella, [496]
Danielssen and Koren, on Gephyrea, [442], [444]
Daphnia, Rotifers attached to, [227]
Dapidia, [225]
Darwin, on Earthworms, [354], [359], [368]
Dasybranchus, [331];
gill, [268]
Dasychone, [338];
gills, [261];